<p class="titletxt">Maintenance</p>

<p><ul> Maintenance </ul></p>

<p>After analyzing the buildings equipment, Tanco Group Ltd will recommend and customize 
a maintenance package to suit each customer's needs and budget. Our maintenance software 
system shows tasks to be performed on a month to month basis with all equipment 
information. This makes sure no piece of equipment gets missed. At the end of every 
maintenance we give the customer a report of how their equipment is running with any 
recommendations. Maintenance will prevent costly service repairs and prevent equipment 
downtime. We offer maintenance including but not limited to:</p>

<p class="highlighttxt">
    Split Systems and Package Units<br>
    Chillers- Reciprocating, Scroll, Screw, and Centrifugal with associated components<br>
    Boilers and Complete Hot Water Systems<br>
    Built up DX Systems and Compressor rebuilds<br>
    Variable Frequency Drives- all Manufacturers<br>
    Fans and Pumping Systems<br>
    Cooling Towers and Evaporative Condensers<br>
    Air Compressors<br>
    Pneumatic Systems and Controls including VAV Boxes<br>
    Computer/Server Room Units<br>
 </p>
 
 <p><em> Find answers to frequently asked questions about maintenance below: </em></p>
 
 <p><b>Why is Preventive Maintenance Necessary?</b></p>
 
 <p>Preventive Maintenance is essential to the proper functioning of HVAC/R equipment. 
 If preventive maintenance is not performed regularly or if it is done ineffectively, 
 the equipment will require extensive and costly repairs at a later date. This is not 
 just a case of "pay me now or pay me later." It is a case of "pay me now or pay me 
 considerably more, later," and lose reliability in the process.</p>
 
 <p>Proper preventive maintenance of HVAC/R equipment requires regular inspections each 
 year. During these inspections, proper operation of the equipment is checked and verified. 
 All mechanical equipment is designed to operate within certain limits. HVAC equipment is 
 no exception, and if not properly maintained, the equipment will exceed its design 
 limitations with the result being equipment failure.</p>
 
 <p><b>Why must we replace air filters?</b></p>
 
 <p>Air conditioning equipment is designed to operate with a specific quantity of air 
 passing over its indoor coil surface. When air filters are not replaced, they clog and 
 become coated with dirt. Similarly, the indoor coils get coated with dirt. This dirt 
 reduces the amount of air through the unit below the design limit, leading to catastrophic 
 failure.</p>
 
 <p>In the cooling mode, if there is not enough air over the indoor coil, the coil temperature 
 drops. When it drops below the freezing point, ice forms on the coil, which further reduces 
 the airflow, which further reduces the coil temperature. The compressor within the unit is a 
 pump, which is designed to pump a vapor. As the airflow through the indoor coil drops, there 
 isn't enough heat being removed from the air passing over the coil to vaporize the liquid 
 refrigerant inside the coil. Thus, instead of receiving a vapor, the compressor receives 
 liquid refrigerant. This is called "liquid slugging". The effect of "liquid slugging" is 
 similar to the effect of pouring liquid into the cylinders of a gas engine. As liquids are not 
 compressible, cylinder pressure exceeds the design limits, of the cylinder, and the valves, 
 connecting rods, pistons, or other internal components are destroyed. The units start out 
 requiring that its filters be replaced. Now it needs a new compressor.</p>
 
<p>In the heating mode, low airflow causes the heat exchanger to overheat. Heat exchangers 
are designed to operate at temperature between 120 F and 200 F. At higher temperatures, the 
heat exchanger oxidizes, its life-span is reduced, or it cracks and breaks. In either case, 
It makes far more sense to replace air filters regularly than to replace a heat exchanger 
costing far more.  In addition if a crack forms in a heat exchanger and it is not discovered 
during a regular maintenance check, dangerous combustion gases can leak into the airstream and 
endanger the building occupants.</p>

<p><b>Why must we replace drive belts?</b></p>
 
 <p>Loose or broken drive belts cause the same problems that dirty filters cause. They cause 
 the airflow through the equipment to be reduced below design limits. In addition, loose drive 
 belts slip on the pulleys. This wears the groove in the pulley so that when the belt is replaced, 
 the new belt is ruined in a short period of time by the worn pulleys. Once again replace the 
 $25.00 belt on a regular basis or spend much more replacing pulleys.</p>

<p><b>Why must we clean condenser coils?</b></p>
 
 <p>Equipment is designed to operate between certain outdoor temperature limits. Cooling and 
 condensing of the refrigerant vapor is designed to occur with a particular volume of air flowing 
 through the condenser at a maximum outdoor ambient temperature. (Usually 115 F) If the finned 
 surfaces of the outdoor coils are fouled with dirt, the ability of these coils to transfer heat 
 is reduced and the airflow through the condenser coil is reduced. When the ability to transfer 
 heat is reduced, the operating temperatures and pressures of the unit increase. A unit, designed 
 to operate at ambient temperatures of 115 F or more, may stop operating at an outdoor temperature 
 of 90 F. Due to the reduced heat transfer capability, the operating temperatures and pressures 
 within the unit exceed the manufacturer's safe limit and the unit shuts down. If the unit does 
 not exceed the manufacturer's limits by enough to shut down, it will continue to run at reduced 
 capacity and efficiency, and at an increased rate of wear due to the increased work load.</p> 
 
 <p><b>Why Inspect Relays and Contactors?</b></p>
 
 <p>Electrical relays are designed to open and close a certain number of times with a particular 
 current load, before the contact points are damaged and relay requires replacement. If more than 
 the design current is passed through this relay due to a motor working too hard, or low voltage 
 conditions, the contact points overheat and become damaged. If the electrical contacts in a 
 contactor (large relay) begin to get pitted, and the contactor is not replaced, eventually the 
 compressor motor or the fan motor controlled by the contactor will burn up and require replacement. 
 Once again, if we exceed the design limitations of the device, or its anticipated life span, 
 additional damage is caused.</p>
 
 <p><b>Why Must We Lubricate Bearings and Rotating Components?</b></p>
 
 <p>Bearings and other rotating parts are designed to have a useful life span of hundreds of thousands 
 of hours, provided they are lubricated at appropriate intervals and are not overloaded due to vibration 
 from defective drive belts or dirty blower wheels. If bearings are not lubricated regularly, they will 
 overheat and seize. When this occurs, the bearings fall apart, and the blower wheel, shaft, and housing 
 are destroyed. This is a prime example of a situation where inexpensive maintenance was neglected with 
 catastrophic results.</p>
 
 <p><b>Why Must We Check the Refrigerant Charge on a Regular Basis?</b></p>
 
 <p>A unit operating with an insufficient refrigerant charge can ruin its compressor via two scenarios. 
 The unit icing up due to a low-pressure condition causes the first type of failure, causing the compressor 
 to fail due to liquid slugging, as described before. The second type of failure is due to the fact that 
 the compressor requires a certain quantity of cool refrigerant vapor to cool its motor windings. If the 
 refrigerant charge is not sufficient, the motor within the compressor will overheat and burn up.</p>
 
 <p>The scenarios described all cause damage to occur slowly, over a period of time, usually without being 
 noticed by the occupants of the conditioned space until catastrophic failure has occurred.</p>
 
 <p>Regularly scheduled preventive maintenance properly performed, in addition to lowering overall annual 
 HVAC/R service costs, and reducing the number of emergency calls due to catastrophic failures, will also 
 result in lower utility costs and reduced greenhouse gas pollutants.</p>
 
 